# DavisMazumderTrends
Data and code to replicate results in "The Decline in Intergenerational Mobility After 1980" by Jonathan M.V. Davis and Bhashkar Mazumder

Documentation for the NLS66 and NLSY79 data is available here: https://www.bls.gov/nls/home.htm

Extracts of underlying survey data can be created here: https://www.bls.gov/nls/home.htm

# Program Organization

The analysis was conducted using Stata/MP 18.0 for Mac (Apple Silicon) Revision 15 May 2023. The code is organized by the file DavisMazumder2023.do which calls separate programs to create each table and figure. 

The main analysis data is contained in the file DavisMazumderData.dta. This data includes full samples for the NLS66 and NLSY79. Sample restrictions are applied in each analysis file. Ranks are generated after smaple restrictions are applied so are re-created in every analysis file.  

We also include several supplementary data files:

- census_data.dta is an extract of decennial census data from the 1940 to 1970 census from IPUMS USA.
- march_cps.dta is an extract of  Current Population Survey Annual Social and Economic Supplement (March Supplement).
- usa_00014.dat is an extract from the 1970 and 1980 1% samples from IPUMS USA.
- nobs.dta is the number of income measures >=1500 between ages 21 and 50 for daughters in the NLS66 and NLSy79. 


# Variable Descriptions

| id_son | NLS66, Young Men Individual Identifier  | 
| id_daughter | NLS66, Young Women Individual Identifier  | 
| hgc | Highest Grade Completed  | 
| byear_dad | Father Birth Year  | 
| byear_mom | Mother Birth Year  | 
| age_firstSurvey | Age in year of first survey  | 
| useDad | Indicator for using income reports in NLS66 Older Men  | 
| survey |  Source of observation  | 
| CASEID |  NLSY79 Individual Identifier  | 
| byear |  Birth Year  | 
| sample_type | Cross-sectional or Supplemental Sample for NLSY79 Observations | 
| share_married |  Share of non-missing income years that youth was married  | 
| women |  Indicator for being a daughter  | 
| surv79 |  Indicator for being an NLSY79 youth  | 
| nsib | Number of siblings | 
| black | Indicator for being Black | 
| white | Indicator for being Non-Black, Non-Hispanic | 
| dad_age_b | Father age on average in years parent income measured | 
| dad_age1_b | Father age in first year parent income measured | 
| mom_age_b | Mother's age on average in years parent income measured | 
| mom_age_at_birth_b | Mother age at birth of respondent | 
| dad_age_at_birth_b | Father age at birth of respondent | 
| mom_outOfRange | Mother not in age range implied by NLS66 sample frame  | 
| dad_outOfRange | Father not in age range implied by NLS66 sample frame  | 
| linkDad |  Indicator for father-child link based on NLS66 sample frame  | 
| linkMom |  Indicator for mother-child link based on NLS66 sample frame  | 
| linkBoth |  Indicator for child being linked to both father and mother based on NLS66 sample frame  | 
| parent1 |  Total parent family income in first survey included in income average (2015$)  | 
| zero_parent1 |  Indicator for first parent income measure equalling exactly zero  | 
| ms_parent1 |  Indicator for missing first parent income measure  | 
| parent2 |  Total parent family income in second survey included in income average (2015$)  | 
| zero_parent2 |  Indicator for second parent income measure equalling exactly zero  | 
| ms_parent2 |  Indicator for missing second parent income measure  | 
| parent3 |  Total parent family income in third survey included in income average (2015$)  | 
| zero_parent3 |  Indicator for third parent income measure equalling exactly zero  | 
| ms_parent3 |  Indicator for missing third parent income measure  | 
| miss0_old | Indicator for missing all three parent income reports | 
| nparent_1500 | Number of parent income reports of >1500 | 
| miss0 | Indicator for having zero parent income reports  of >1500 | 
| tot0_min0 | Family income in parent generation requiring income reports be >0 | 
| ltot0_min0_66 | Log of tot0_min interacted with indicator for NLS66 | 
| ltot0_min0_79 | Log of tot0_min interacted with indicator for NLSY79 | 
| tot0_min1000 | Family income in parent generation requiring income reports be >1000 | 
| ltot0_min1000_66 | Log of tot1000_min interacted with indicator for NLS66 | 
| ltot0_min1000_79 | Log of tot1000_min interacted with indicator for NLSY79 | 
| parent1_min1500 | First parent income report if >1500 | 
| parent2_min1500 | Second parent income report if >1500 | 
| parent3_min1500 | Third parent income report if >1500 | 
| tot0_min1500 | Average of parent income reports that are >1500 | 
| ltot0_min1500_66 | Log of tot1500_min interacted with indicator for NLS66 | 
| ltot0_min1500_79 | Log of tot1500_min interacted with indicator for NLSY79 | 
| tot0_min2500 | Average of parent income reports that are >2500 | 
| ltot0_min2500_66 | Log of tot2500_min interacted with indicator for NLS66 | 
| ltot0_min2500_79 | Log of tot2500_min interacted with indicator for NLSY79 | 
| faminc0_oldbase | Average family income using non-missing family income reports | 
| loginc66_oldbase | Log of faminc0_oldbase interacted with indicator for NLS66 | 
| loginc79_oldbase | Log of faminc0_oldbase interacted with indicator for NLSY79 | 
| faminc0 | Main parent income measure, equals tot0_min1500 | 
| lfaminc0 | Log of faminc0 | 
| loginc66 | Log of faminc0 interacted with indicator for NLS66 | 
| loginc79 | Log of faminc0 interacted with indicator for NLSY79 | 
| kid_age_parent | Average child age in years parent income is measured | 
| kid1 |  Total child family income in first survey included in income average (2015$)  | 
| kid2 |  Total child family income in second survey included in income average (2015$)  | 
| kid3 |  Total child family income in third survey included in income average (2015$)  | 
| zero_kid1 |  Indicator for first child income measure equalling exactly zero  | 
| ms_kid1 |  Indicator for missing first child income measure  | 
| zero_kid2 |  Indicator for second child income measure equalling exactly zero  | 
| ms_kid2 |  Indicator for missing second child income measure  | 
| zero_kid3 |  Indicator for third child income measure equalling exactly zero  | 
| ms_kid3 |  Indicator for missing third child income measure  | 
| miss1_old | Indicator for having zero non-missing child income reports | 
| nkid_1500 | Number of child income reports >1500 | 
| miss1 | Indicator for having zero child income reports >1500 | 
| miss1_early | Indicator for having zero early career income reports >1500 | 
| miss1_prime | Indicator for having zero prime career income reports >1500 | 
| kid_age | Average child age in years child income is measured | 
| tot1_min0 | Average of child income reports that are >0 | 
| ltot1_min0 | Log of ltot1_min0 | 
| tot1_min1000 | Average of child income reports that are >1000 | 
| ltot1_min1000 | Log of ltot1_min1000 | 
| kid1_min1500 | First child income report if >1500 | 
| kid2_min1500 | Second child income report if >1500 | 
| kid3_min1500 | Third child income report if >1500 | 
| tot1_min1500 | Average of child income reports that are >1500 | 
| ltot1_min1500 | Log of tot1_min1500 | 
| tot1_min2500 | Average of child income reports that are >2500 | 
| ltot1_min2500 | Log of tot1_min2500 | 
| faminc1_oldbase | Average of all non-missing child generation family income measures | 
| lfaminc1_oldbase | Log of faminc1_oldbase | 
| faminc1 | Average of all child generation family income reports >1500 | 
| lfaminc1 | Log of faminc1 | 
| faminc1_early | Average of all early career child generation family income reports >1500 | 
| lfaminc1_early | Log of faminc1_early | 
| faminc1_prime | Average of all prime career child generation family income reports >1500 | 
| lfaminc1_prime | Log of faminc1_prime | 
| owninc | Average of respondent's own income reports >750 | 
| lown | Log of owninc | 
| nown_l750 | Number of respondent's own income reports >750 | 
| miss1_l750 | Indicator for having no own income reports >750 | 
| spouse_inc |  Average spouse wage and salary income for child (2015$)  | 
| spouse_age |  Average spouse age in years child income is measured  | 
| weight_first | Survey weight in first wave of survey | 
| weight | Same as weight_first, main weight used in paper | 
| weight_incFirst | Survey weight in first year child income measured | 
| weight_incLast | Survey weight in last year child income measured | 
| weight_incAvg | Average survey weight in years child income measured | 
| all_parent |  Indicator for having no missing or zero parent income reports  | 
| all_parent_1500 | Indicator for all parent income reports being at least $1500 | 
| all_kid |  Indicator for having no missing or zero child income reports  | 
| all_kid_1500 | Indicator for all child income reports being at least $1500 | 
| married | 100*Indicator for child being married across all interviews where child income is measured (x100)  | 
| unmarried | 100-married | 
| hgc_parent | Parents' highest grade completed | 
| hhid | Household Identifier | 
| n | Equals 1 for everyone, used for getting weighted counts | 


